Environmental Risk Assessment (ERA) of diclofenac and ibuprofen: A public health perspective

•ERA was carried out for two NSAIDs in a Brazilian public health system.•Public health service caused environmental risk for diclofenac in 12 cities.•Ibuprofen usage in public health represented environmental risk in 51 cities.•Findings are relevant to support environmental politics on medicines. Non-steroidal anti-inflammatory drugs (NSAIDs) have been widely used in human and veterinary medicine, representing potential aquatic environmental contamination. This study aimed to perform an Environmental Risk Assessment (ERA) of NSAIDs diclofenac (Dic) and ibuprofen (Ibu) in cities of the state of Paraná, Brazil, over the course of three years, by using available data from the Brazilian Public Health System. The environmental risk (ER) was assessed by employing the European Medicines Agency (EMeA) approach, and predicted environmental concentrations (PECs) were calculated. The refined PECs considered the drug metabolism and the excretion data, and also the sewage treatment plant removal rates of biological filters and activated sludge processes to define environmental scenarios. References to the predicted no effect concentration (PNEC) for these pharmaceuticals were considered, and the PEC/PNEC ratio was calculated; ratio values ⩾1 suggested an ER. Environmental risk was conducted on several cities, and the lack of an adequate sanitation system in the majority of Paraná cities forecasts a significant concern with the exposure to possible environmental damages in those cities. The high PEC/PNEC ratios in several cities showed that current usage patterns of these drugs constitute an environmental issue in need of resolution by health and environmental authorities.